Van der Waals interaction in Density Functional Theory (when the weakest player is a game-changer)
Dr. Predrag Lazic
University of Missouri-Columbia
Density functional theory (DFT) has been a tool of choice in modern ab-initio calculations for decades. It proved invaluable in computational chemistry, surface science, and
materials science. However, until relatively recently it did not include the weak van der Waals (vdW) interactions, except empirically.
With the advent of 2D materials, such as graphene, van der Waals interaction became essential for the accurate description of such systems.
In this seminar, we will show the introduction of the first vdW density functional and demonstrate how it plays a crucial role in several real-word systems.
Namely, we will show the crucial role of the vdW interaction in the famous DFT problem from surface science – called the CO puzzle where standard DFT fails to predict correctly the
adsorption site for the CO molecule on the Pt(111) surface.
Next, we will show the study of Cs and Li atoms intercalation under graphene on Ir(111) surface. The standard DFT fails in reproducing even the qualitative description of those experimentally very well studied systems.
And finally, we will use the DFT with van der Waals interactions to explain the experiment of growth of monolayer of MoS2 on a sapphire surface. Even though this problem initially seemed like a straightforward DFT-vdW calculation it turned out to be a tough nut to crack.
Hosted by Prof. Assaf
All interested persons are invited to attend remotely—email physics@nd.edu for information.